Global Sea Level Essay

1590 Words 7 Pages
According to the National Snow and Ice Data Centre (an American institution), “more than 100 million people currently live within 1 [metre] of mean sea level”, meaning that close to 100 million people could and will be displaced from their homes within the next few hundred years, due to sea level rise (2010). There are several factors that contribute to the rise of global sea-level, both directly (warming oceans, expansion of ocean particles and melting glaciers) and indirectly (global warming and the loss of ice shelves). While ice shelves don’t directly contribute to the rising of sea-level, they play an important part in acting as a resistance towards the runoff water from glaciers to stop this water from reaching the ocean. The buttressing …show more content…
Greenhouse gases warm the Earth’s atmosphere, with most of this excess heat being absorbed by the top 700 metres of the ocean (NASA, 2016). This heating of the oceans’ surface causes the expansion of water particles, resulting in a small amount of sea-level rise (Schneider, 1997). Melting glaciers and ice sheets are noted as the biggest single contributor to rising sea-levels, with about 40% of current sea level rise caused by this melting (Atkins, Crampton and Newnham, 2014). Most scientific and government reports on rising sea level base their predictions on the year 2100, such as the Intergovernmental Panel on Climate Change, as to predict further into the future would compromise the accuracy of the predictions. How we act today on climate change will affect the severity and effects of climate change in 2100 and from then onwards (Our World, …show more content…
Calving is described as a ‘natural event’, which produces icebergs by rifting, usually caused by meltwater ponding (Davies, 2014). Calving is also a result of the “formation of large crevasses” which occur as a result of the warming ocean thinning the ice shelves (Scripps Institution of Oceanography, 2016). While they play an important role in calving, melt ponds have also been linked to the ‘disintegration’ mode of ice shelf breakups, with studies observing that ice shelves with melt ponds disintegrated at a much faster pace than those without (Bohlander, Scambos, Shuman and Skvarca, 2004). Disintegration is the mode of ice shelf breakup that has been brought about by climate change. The majority of the depleting ice shelves are located on the Antarctic Peninsula, which has had a 2.5 degrees’ Celsius increase in temperature since 1950 (National Snow & Ice Data Centre, 2010). Two separate processes of disintegration have been observed by scientists, both of which occur due to the warming of the atmosphere and the ocean: warm air melts the ice on the surface of the shelf and travels through cracks, which “deepen, erode and expand those cracks”, and the warming of the ocean melts the ice shelf from beneath, thinning it and making it susceptible to cracking. The rapid melting of sea ice is also attributed to the rapid decline of ice shelves, as the sea ice usually

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